A server can be successfully shut down when electric power is supplied from a power supply device during a power failure. A power supply device to be used for this application is put to practical use as an uninterruptible power supply system. The uninterruptible power supply system incorporates a secondary battery that supplies a server with operation power. The uninterruptible power supply system supplies electric power after it detects a power failure until the server completes a shutdown operation. A power supply device to be used for this application needs to supply a server as a load with a large electric power although supplying time is short. Furthermore, not only in the uninterruptible power supply system, but also in power supply devices for supplying a large electric power, for example, a power supply device for a vehicle, it is necessary to increase an electric current capacity of a power supply connector and an output lead connected to the power supply connector.
The power supply connector having a large electric current capacity is required to increase a contact pressure by using a thick metal plate for an elastic contact that is brought into contact with a power line. A power supply connector having a thick metal plate is attached in a floating state, and can be electrically connected to a power line at a load side stably and smoothly. This is because relative displacement between the elastic contact of the power supply connector and the contact at the load side can be absorbed by moving the power supply connector that is in a floating state. This power supply connector achieves characteristics of moving to a position in which power supply connector can be smoothly linked to the load side, and being stably connected to the position.
In order to connect a power supply connector reliably and stably, devices in which the power supply connector is attached in a floating state have been developed (see PTLs 1 to 4).